Atrial fibrillation (or AF) is the most common cardiac arrhythmia or abnormal heart rhythm suffered by human patients. AF develops in the two upper chambers or atria of the heart, and is so-named owing to the fibrillation or quivering of the heart muscles of the atria (as opposed to the normal coordinated contraction of the atria). Patients suffering from AF often have heartbeats that do not occur at regular intervals, or they may present an absence of normal P-waves in their electrocardiograms (ECGs). The risk of AF increases with age, and it is estimated that 8% of people over 80 suffer from AF.
In AF, the normal electrical impulses generated by the sino-atrial (SA) node are overwhelmed by disorganized electrical impulses that originate in the atria and pulmonary veins, leading to the conduction of irregular impulses to the ventricles that generate a heartbeat. The result is an irregular heartbeat, which may occur in episodes lasting from minutes to weeks, or that may occur continuously over a period of years. Atrial fibrillation has a pronounced tendency AF to become chronic, which in turn leads to an increased risk of severe health consequences such as cerebrovascular accident (CVA, or stroke) and death.
Atrial fibrillation is often asymptomatic, and in the general case is not life-threatening. Atrial fibrillation can result in palpitations, fainting, chest pain, congestive heart failure, and a generally decreased quality of life. Patients suffering from AF usually have a significantly increased risk of stroke (up to seven times that of the general population). Stroke risk increases during AF because blood may pool and form clots in the poorly contracting atria, especially in the left atrial appendage (LAA). Atrial fibrillation is known to be a leading cause of stroke.
Detecting or diagnosing AF in a patient typically requires the acquisition, processing and analysis of ECGs from the patient, which in turn usually involves the employment of complicated, costly and specialized medical equipment. Such medical equipment is often unavailable to or too costly for general practitioners and health care providers. Moreover, such medical equipment must often be operated by medical specialists, which further decreases the possibility of widespread and effective diagnosis of AF among the general population. Given the prevalence of AF in the general population, and the serious and debilitating consequences of AF, what is needed is a more economic, easier and quicker means of diagnosing AF in patients, especially in the context of patients visiting their general practitioner or health care provider.